I have a 72 bus with a 1700. I have never needed to look inside the cooling ducts until now when I replaced the oil cooler. My question is should I leave the thermostat flaps like they are and have been for years (driver flap down and pass up) or should I wire it open? It looks like the air has not been passing over the cooler at all really. I could maybe rig up something to allow me to move it manually. Thanks in advance

From your description, it sounds like you have them open already. The way they work isn't intuitive at all. Driver flap goes down to direct more air over the cooler and the pass goes up to send more to the cylinders.

I have the bracket,the wire and nut. If i have looked correctly I believe th flaps are in the warm up position until the thermostat heats up then pulls the cable that is attached to the flaps and moves them into the operating temp position. Thus pushing air thru the cooler. My flap is laying on my cooler and I do not see how air could pass thru it

Check your flaps they can be bent and easily damaged if some one has gorilla gripped it at some time in its life. Also make sure everything is in place and installed completly. The main flap rod should be spring loaded.

I believe that is the "hot" position. that's where mine are, if you don't have a thermostat, that's how you want them to be. That way the flap can grab some of the incoming air and force it into the oil cooler.